The extreme performance characteristics of modern day grand prix/racing motorcycles have led manufacturers to develop very stiff front end packages, designed to bear huge loads primarily during heavy braking. During this condition, the rearward force on the front tire's contact patch presses rearward on the lower portion of the forks at the axle and the inertia of the motorcycle's mass presses forward on the upper portion of the forks at the triple clamps. The resulting flex in the longitudinal direction (direction of travel of the motorcycle) is minimized by increasing the rigidity of the forks.
This increased stiffness of the front forks solves the problem of longitudinal flexing during braking. However, the compromise demanded by a stiffer front end is the appearance of chatter, or vibrations resulting from momentary reductions of traction, particularly during turns. Severe leaning angles typically result from motorcycles negotiating these turns and produce conditions conducive to chatter. When the motorcycle is leaning, the tire's contact patch shifts from the center to side, but the forces from the road are in the vertical direction. Upon hitting little bumps, the vertical force transfers onto the motorcycle mostly laterally. The inability of stiff forks to flex in the lateral direction causes the bumps and imperfections of the road surface to lift up the vehicle, without any elastic restorative forces of the forks being able to maintain pressure of the tire against the road surface.
This problem leads to the vehicle losing contact with the road surface which can result in chatter. Being vibration that resonates from the front tire up to the chassis until dampened, chatter is a nuisance to riders and decreases motorcycle performance. Therefore, it is desirable to maintain longitudinal stiffness in the front end for rigidity under heavy breaking and at the same time, reduce chatter for improved handling of the motorcycle.